safety vs safety pin

safety

noun
  • A mechanism on a weapon or dangerous equipment designed to prevent accidental firing. 

  • An instance of a player being sacked or tackled in the end zone, or stepping out of the end zone and off the field, resulting in two points to the opposite team. 

  • The condition or feeling of being safe; security; certainty. 

  • Any of the defensive players who are in position furthest from the line of scrimmage and whose responsibility is to defend against passes as well as to be the tacklers of last resort. 

  • A safety squeeze. 

  • Preservation from escape; close custody. 

verb
  • to secure a firing pin, as in guns, to keep the gun from firing 

  • To secure (a mechanical component, as in aviation) to keep it from becoming detached even under vibration. 

safety pin

noun
  • The pin of a hand grenade, which prevents accidental detonation. 

  • A pin in the form of a clasp, which has a guard to cover the sharp point; used to join two pieces of fabric, etc., together temporarily. 

How often have the words safety and safety pin occurred in a corpus of books? (source: Google Ngram Viewer )